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运用脉冲电沉积技术,将Zn2+,Pb2+,Bi3+,La3+共沉积制备多元合金,以此来改善锌电极的电化学性能。利用XRD,SEM和EDS对多元合金进行了结构表征,结果显示共沉积Pb,Bi,La元素进入了锌中形成置换型固溶体。通过极化曲线、塔菲尔曲线、循环伏安曲线、交流阻抗谱和充放电循环实验,研究了共沉积元素对锌电极在6 mol.L-1KOH溶液中电化学性能的影响,结果表明Zn-Pb-La-Bi四元合金电极的腐蚀电流为107.68 mA,致钝电流为68.85 mA,与锌电极相比,腐蚀程度降低了66.834%,阴阳极峰电流的衰减最慢,电化学阻抗也较大。以Zn-Pb-La-Bi四元合金粉为负极或锌粉为负极,组装二次碱性锌镍电池,充放电循环实验表明,最高容量分别为130.8,121.8 mAh.g-1,循环20次,电池衰减百分数分别为2.68%,6.65%。结果表明本文制备的8种合金电极的综合性能顺序为Zn-Pb-La-Bi>Zn-Bi-La>Zn-Pb-Bi>Zn-Pb-La>Zn-Bi>Zn-La>Zn>Zn-Pb,综合性能最佳的Zn-Pb-La-Bi合金有望代替汞齐化锌用作二次碱性锌镍电池负极。
Electrodeposition of Zn2 +, Pb2 +, Bi3 + and La3 + was co-deposited to prepare the multi-element alloy by pulse electrodeposition technique to improve the electrochemical performance of zinc electrode. XRD, SEM and EDS were used to characterize the multi-alloy structure. The results show that Pb, Bi and La co-deposited into the zinc to form a substitutional solid solution. The effects of co-deposition elements on the electrochemical performance of zinc electrode in 6 mol.L-1 KOH solution were investigated by polarization curves, Tafel curves, cyclic voltammetry curves, AC impedance spectra and charge-discharge cycles. The results showed that Zn The corrosion current of -Pb-La-Bi quaternary alloy electrode is 107.68 mA and the induced blunt current is 68.85 mA. Compared with the zinc electrode, the corrosion degree of -Pb-La-Bi alloy decreases by 66.834%, and the peak current decay of cathode and anode is the slowest. The electrochemical impedance Larger. With Zn-Pb-La-Bi quaternary alloy powder as negative electrode or zinc powder as negative electrode, secondary alkaline zinc-nickel batteries were assembled. The charge-discharge cycle experiments showed that the maximum capacities were 130.8, 121.8 mAh.g-1, Times, the percentage of battery degradation were 2.68%, 6.65%. The results show that the comprehensive performance sequence of the 8 kinds of alloy electrodes prepared in this paper is Zn-Pb-La-Bi> Zn-Bi-La> Zn-Pb-Bi> Zn-Pb-La> Zn-Bi> Zn-La> Zn-Pb, the best overall performance of Zn-Pb-La-Bi alloy is expected to replace the amalgam zinc secondary alkaline zinc-nickel battery cathode.